The Internet is growing at an incredible rate. Much of this growth is
attributed to Internet users who can't afford high-speed permanent
network connections and who use protocols such as SLIP, PPP, or UUCP
to dial in to a network provider to retrieve their daily dose of email
and news.

This chapter is intended to help all people who rely on modems
to maintain their link to the outside world. We won't cover the
mechanics of how to configure your modem (the manual that came with it
will tell you more about it than we can), but we will cover most of
the Linux-specific aspects of managing devices that use serial
ports. Topics include serial communications software, creating the
serial device files, serial hardware, and configuring serial devices
using the setserial and stty
commands. Many other related topics are covered in the Serial HOWTO
by David Lawyer.[1]